1. Pulse the Nutter Butter cookies (reserve 1/2 cup) in a food processor until fine crumbs, or crush in a zip-top bag with a rolling pin. Mix with the melted butter until every crumb is moistened. Press firmly and evenly into the bottom of a 9×13-inch dish using a flat-bottomed glass to compact. Refrigerate while you make the next layer.

2. Beat the softened cream cheese, peanut butter, and sifted powdered sugar together on medium speed for 2 to 3 minutes until completely smooth. Fold in half of the thawed whipped topping with a rubber spatula using gentle sweeping motions — do not stir vigorously or the mousse loses its airy texture. Spread evenly over the chilled cookie crust.

3. Whisk both boxes of instant chocolate pudding mix with the cold whole milk and espresso powder if using for 2 full minutes until thick. Let stand 2 more minutes until set. Spread the chocolate pudding evenly over the cream cheese layer all the way to the edges.

4. Spread the remaining whipped topping over the chocolate pudding in a thick, smooth, even layer. Scatter the reserved crushed Nutter Butter cookies across the surface. Drizzle the melted peanut butter in long ribbons, then drizzle the melted chocolate or chocolate syrup over the top.

5. Cover with plastic wrap and refrigerate for a minimum of 4 hours — overnight produces the best results. The cookies soften to a tender, almost cake-like consistency and all the layers meld together perfectly.

6. Slice into squares using a sharp knife wiped completely clean between every single cut. Use a flat spatula to lift each piece cleanly from the dish. Serve cold directly from the refrigerator.